Apparatus for affixing a flange to a tube



Oct. 10, 1967 M. J. LAVERTY 3,345,730

APPARATUS FOR AFFIXING A FLANGE TO A TUBE Original Filed Oct. 16, 1963 vTlc'l.

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/Z/////// V /L\ INVENTOR i/imernv J. A/wmerv' ATTORNEY United StatesPatent 3,345,730 APPARATUS FOR AFFIXING A FLANGE TO A TUBE Martin J.Laverty, Jericho, N.Y., assignor to Murray 7 2 Claims. (Cl. 29-24352)This is a division of application Ser. No. 316,613, filed Oct. 16, 1963,now abandoned.

This invention relates to a method and apparatus for aflixing a flangeto a tube. More specifically, the invention is directed to techniquesfor aflixing a flange to a tube without causing a reduction to theinternal diameter of the tube.

In Patent No. 3,037,800, assigned to Murray Manufacturing Corporation,techniques are described for atfixing a flange to one end of a tube. Thetube and flange described in that patent and the tube and flangedescribed and claimed in the instant application are for use with anelectromagnetic circuit breaker. In the circuit breaker, the tube ishydraulically filled and hermetically sealed.

The internal dimensions of the tube are critical because a magnetic polepiece travels axially within the tube during operation of the circuitbreaker.

In the aforementioned patent, the external flange is aflixed to thecircumferential area adjacent the closed end of the tube. The flange isstaked to the tube by deforming a portion of the flange close to thetube, so as to displace part of the flange material into the wall of thetube. A slug is located internally of the tube adjacent the flange andwedged in place. Although the invention described in the aforementionedpatent is generally satisfactory, it is limited to an assembly where theflange is aflixed at the closed end of the tube.

v Accordingly, it is the object of this invention to provide a techniquefor aflixing a flange to a tube anywhere along its perimeter and withoutthe requirement of a slug on the inside of the tube.

It is a further object of the invention to provide a technique foraffixing a flange to a tube without causing any reduction in theinternal diameter of the tube.

In accordance with an aspect of the invention, the flange is located adesired distance from one end of the tube which may beeither the open orclosed end. The flange is an annular member closely surrounding thecircumference of the tube. An expansible punch is inserted into the tubeand has a die portion shaped to form rims on opposite sides of theflange; the rims are sufficient to stake the flange to the tube. Thepunch is expanded to produce the rims and then collapsed and removedfrom the tube.

The above mentioned and other features and objects of this invention andthe manner of attaining them will become more apparent and the inventionitself will be best understood by reference to the following descriptionof an embodiment of the invention taken in conjunction with theaccompanying drawings, wherein:

FIG. 1 is a cross-sectional view showing the tube, punch and flangeprior to the expansion of the punch;

FIG. 2 is a similar view showing the punch in the. expanded condition;

FIG. 3 is a side view of the punch; and

FIG. 4 is a top view of the punch.

Referring first to FIG. 1, there is illustrated a tube 1, preferablymade of brass or other suitable malleable material. The tube 1 islocated preferably automatically within a tube holder 2, which isdesigned to support the tube during the staking of the flange to thetube.

3,345,730 Patented Oct. 10, 1967 The flange}, preferably made of steel,is an annular member having a diametral opening just slightly greaterthan the external diameter of the tube 1. The flange is positionedaround the tube and is supported by the arms 4 of the tube holder 2. Thelocation of the flange on the tube is predetermined, and by the lengthof the tube holder is selected accordingly.

, The flange 3 is staked to the tube 1 by means of a punch 5. The punchcomprises an expansible body portion 6 and an actuating rod 7 whichproduces the desired expansion.

The expansible body portion is shown in detail in FIGS. 3 and 4 and isin the form of a hollow cylinder slotted longitudinally at quadrantintervals to provide the desired expansibility. As shown in the drawing,the punch body 6 is hollow and the lower portion of the punch body isformed with an enlarged bore which joins the upper hollow portion of thepunch; the openings are joined by a ledge 8.

The upper face of the punch body 6 is in the form of a die containingpairs of axially spaced projections 9 and 10. When the punch is fullyinserted into the tube 1 so that the bottom of the punch comes to reston the base of the tube, or equivalent support if the tube is openended, the pairs of projections 9, 10 are located approximately in linewith the upper and lower faces of the flange, respectively. The spacebetween the projections 9 and 10 is approximately equal to the thicknessof the flange 3.

The punch body is expanded by the actuating rod 7, which comprises acylindrical position 12 having an external diameter less than theinternal diameter of the punch body 6. The length of the cylindrical rod12 is approximately equal to the length of the hollow portion of thepunch body, as shown in FIG. 1. The cylindrical rod 12 is integral withor connected to a tapered rod 13 whose diameter gradually increases to adimension suflicient to produce the desired expansion of the punch.

In the unactuated condition, as shown in FIG. 1, the cylindrical rod 12is inserted in the punch body 6. The staking is produced by actuatingthe rod in the downward direction, as shown in FIG. 2, so that, thetapered portion 13 enters into the hollow portion of the punch body 6.The die face is gradually extended and the projections 9 and 10 areforced radially outwardly to form rims on opposite sides of the flangefaces.

The actuating rod 5 is coupled to the punch body 6 very simply by meansof a screw which has a head engaging the ledge 8 between the differentsized openings in the punch body 6. The coupling, therefore, permitsaxial freedom of the actuating rod in the downward direction, as shownin FIG. 2. The enlarged bore diameter is, of course, greater than thediameter of the screw head.

Upon withdrawal of the actuating rod 5, the expansible body collapses toits normal diameter upon removal of the tapered arm 13. Furtherwithdrawal of the arm 5 causes the screw head to engage the ledge 8 andcarry with it the punch body 6. The tube and flange are thus stakedtogether and the assembly is removed from the tube holder 2.

It is apparent from the foregoing description that the invention isrelatively simple, requiring only a few parts, and is capable ofproducing the desired staking without reducing the internal diameter ofthe tube.

While the foregoing description sets forth the principles of theinvention in connection with specific apparatus, it is to be understoodthat this description is made only by way of example and not as alimitation of the scope of the invention as set forth in the objectsthereof and in the accompanying claims.

What is claimed is:

1.' Apparatus for aflixing an external flange to a metal tube,comprising an expansible punch having an external diameter slightly lessthan the inside diameter of said tube, whereby the punch may be insertedinto said tube, one end of said punch being in the form of a die andhaving axially spaced projections, the axial separation between saidprojections being approximately equal to the thickness of said flange,said punch being in the form of a tube, the upper portion of which islongitudinally slotted to provide radial expansibility, tubular meanshaving means associated therewith for engaging said punch and said tubeend, for locating said flange around said tube a given distance from theend of the tube and for limiting the movement of said punch during theexpansion thereof, the flange fitting snugly around said tube, and punchexpanding means attached to said punch capable of expanding said die tocause said projections to deform the tube metal outwardly and therebystaking said flange, said punch expanding means comprising a rod, afirst portion of said rod being located inside the slotted portion ofsaid punch when said punch is in the unexpanded condition, a secondportion of said rod being tapered to produce the desired expansion whenthe tapered portion is inserted into said punch, and means coupling anend 0t said rod to said punch with freedom of axial movement of said rodin the punch expanding direction, but engaging said punch when it isdesired to remove said punch from the tube.

2. The apparatus according to claim 1, wherein said punch is providedwith an enlarged radial bore at the end opposite the die, the length ofsaid bore being greater than the length of said tapered portion of saidrod, and said coupling means comprises a member attached to the end ofsaid first portion of said rod and extending into said enlarged bore andhaving a radial width greater than the internal diameter of said tube,whereby the rod may be moved axially into said bore, but upon withdrawalsaid member engages the ledge between the bore and tube diameter and therod carries said punch with it.

References Cited UNITED STATES PATENTS CHARLIE T. MOON, PrimaryExaminer.

1. APPARATUS FOR AFFIXING AN EXTERNAL FLANGE TO A METAL TUBE, COMPRISINGAN EXPANSIBLE PUNCH HAVING AN EXTERNAL DIAMETER SLIGHTLY LESS THAN THEINSIDE DIAMETER OF SAID TUBE, WHEREBY THE PUNCH BEING IN THE FORM OF ADIE AND ONE END OF SAID PUNCH MAY BY INSERTED INTO SAID TUBE, HAVINGAXIALLY SPACED PROJECTIONS, THE AXIAL SEPARATION BETWEEN SAIDPROJECTIONS BEING APPROXIMATELY EQUAL TO THE THICKNESS OF SAID FLANGE,SAID PUNCH BEING IN THE FORM OF A TUBE, THE UPPER PORTION OF WHICH ISLONGITUDINALLY SLOTTED TO PROVIDE RADIAL EXPANSIBILITY, TUBULAR MEANSHAVING MEANS ASSOCIATED THEREWITH FOR ENGAGING SAID PUNCH AND SAID TUBEEND, FOR LOCATING SAID FLANGE AROUND SAID TUBE A GIVEN DISTANCE FROM THEEND OF THE TUBE AND FOR LIMITING THE MOVEMENT OF SAID PUNCH DURING THEEXPANSION THEREOF, THE FLANGE FITTING SNUGLY AROUND SAID TUBE, AND PUNCHEXPANDING MEANS ATTACHED TO SAID PUNCH CAPABLE OF EXPANDING SAID DIE TOCAUSE SAID PROJECTIONS TO DEFORM THE TUBE METAL OUTWARDLY AND THEREBYSTAKING SAID FLANGE, SAID PUNCH EXPANDING MEANS COMPRISING A ROD, AFIRST PORTION OF SAID ROD BEING LOCATED INSIDE THE SLOTTED PORTION OFSAID PUNCH WHEN SAID PUNCH IS IN THE UNEXPANDED CONDITION, A SECONDPORTION OF SAID ROD BEING TAPERED TO PRODUCE THE DESIRED EXPANSION WHENTHE TAPERED PORTION IS INSERTED INTO SAID PUNCH, AND MEANS COUPLING ANEND OF SAID ROD TO SAID PUNCH WITH FREEDOM OF AXIAL MOVEMENT OF SAID RODIN THE PUNCH EXPANDING DIRECTION, BUT ENGAGING SAID PUNCH WHEN IT ISDESIRED TO REMOVE SAID PUNCH FROM THE TUBE.